Method of making ear stoppers



June 14, 1955 J. J. CANTOR 2,710,427

METHOD OF MAKING EAR STOPPERS Filed Nov. 19, 1953 2 Sheets-Sheet l 1N VEN TOR.

E615 BY @4164 June 14, 1955 J. J. CANTOR METHOD OF MAKING EAR STOPPERS 2 Sheets-Sheet 2 Filed Nov. 19, i953 M46296 J. CfiA/I'QQ,

INVENTOR.

Y Mg) fun 2,710,427 Patented June 14, 1955 METHOD OF MAKING EAR STOPPERS Jacob J. Cantor, Los Angeles, Calif.

Application November 19, 1953, Serial No. 393,197

1 Claim. (Cl. Ill-58.3)

This invention has to do with structure dampening '1 sound, and more particularly with stoppers that may be inserted in the human ear. It has been determined through scientific and practical research that the ear drum vibrates the minutest amount when sound is imposed thereon and by virtue of this fact sound is conducted to the inner ear. In order to reduce the amount of sound reaching the inner car it has been determined that it is necessary to stop or retard the vibration of the ear drum. This invention is predicated on the idea that no sound can be produced unless mechanical or intermolecular friction is present.

Therefore, one of the principal objects of this invention is to provide a gas filled ear stopper that will retard the movement of the ear drum, reduce the conduction of sound to the middle and inner ear, and have a minimum amount of friction between the ear stopper and the walls of the external canal.

Another object of this invention is to provide an ear stopper that will fit snugly in the external canal of the human ear in such a manner as to cause the sealing of the external canal and at the same time compress the air in the canal and retard the movement of the ear drum.

Another object of this invention is to provide an ear stopper having relatively thin, seamless walls that is hermetically sealed and gas filled and will conform to the configuration of the external canal of the human ear and cause a greater than atmospheric pressure to be exerted in the external canal between the innermost end of the ear stopper and the ear drum.

Another object of this invention is to provide an ear stopper wherein the confined gases in the hermetically sealed thin-Walled envelope will create sufi'icient pressure on the walls of the envelope to distort said envelope, thereby compressing the trapped air in' ear canal and tending to depress the tympanicmembrane.

Another object of this invention is to provide an ear stopper, the rear end of which is distorted when the stopper is placed in the external canal that will cause the same to conform to the configuration of the external canal, resulting in a greater than atmospheric pressure being exerted within the human ear.

Another object of this invention is to provide an ear stopper wherein the compressed portions of the thinwalted, gas-filled envelope will tend to expand the uncompressed portions when the ear stopper is inserted into the external ear canal and by virtue of this fact the ear stopper is self-returning.

Another object of this invention is to provide an ear stopper having no mechanical movement between its parts and having structure thereon that will limit the inward movement or insertion of the-ear stopper into the external canal, and structure that will enable the ear stopper to be removed from the human ear.

A further object of this invention is to provide an ear stopper wherein the materials composing the ear stopper have a' minimum coefficient of friction.

A further object of this invention is to provide an ear stopper which will enfold the cartilaginous protuberances of the external ear canal and force itself down into the rugae which form the walls of the normal ear canal.

Another principal object of this invention is to pro vide a method of mass molding, coagulating and curing of ingredients that are utilized to form ear stoppers.

A yet further object of this invention is to provide a method of making ear stoppers that have relatively thin Walls in order that the stoppers will conform to the configuration of the external canal of a human ear.

A still further object of this invention is to provide a method of making ear stoppers for the human ear that will have a gas entrapped and retained Within the ear stopper.

With the foregoing and other objects in view, which will be made manifest in the following detailed description and specifically pointed out in the appended claim, reference is had to the accompanying drawings for an illustrative embodiment of the invention, wherein:

Figure 1 of the drawings is a fragmentary sectional view of one section of the mold used for molding ear stoppers and having placed therein ingredients that are utilized for making ear stoppers;

Fig. 2 is a fragmentary sectional view illustrating two sections of the mold placed in juxtaposition;

Fig. 3 is a fragmentary sectional view illustrating th manner of securing the two sections of the mold together and showing in dotted lines the flow of the ingredients from one section of the mold to the other section;

Fig. 4 is a fragmentary sectional view illustrating the configuration of the ear stopper when the ingredients used for making the same have occupied each section of the mold;

Fig. 5 is a perspective view illustrating the ear stopper of this invention;

Fig. 6 is a fragmentary sectional view illustrating the initial position of the press and mold prior to the ingredients occupying each section of the mold, as illustrated in Fig. 3 of the drawings;

Fig. 7 is a View similar to Fig. 6, but illustrating the mold and press rotated and including the position of the ingredients assumed in the mold, as illustrated in Fig. 3 of the drawings; and

'Fig. 8 is a fragmentary sectional view illustrating the ear stopper of Fig. 5 inserted into the external canal of a human ear.

Referring to the accompanying drawings wherein similar reference characters designate similar parts throughout, 10 broadly designates a seamless ear stopper which comprises an elongated, hollow, envelope 12 having a gas filled chamber 14 therewithin which is entirely closed throughout. The ear stopper 10 has a mass which is sufficient to impede, reflect and repel the sounds that normally occur to those persons subjected to excessive noises.

One end 16 of envelope 12 is tapered to facilitate the entrance of the ear stopper into the human ear 18. The end 20 opposed to end 16 has extending therefrom a projection 22 that enables the wearer of the ear stopper 1!) to remove the same from the ear 18.

Formed on the envelope 12 and between the two ends 16 and 2G is an arcuate tab 24 that acts as a stop to limit the amount of the ear stopper 10 that may be inserted into the external canal 26 of the human ear 18. V

Chamber v14 has hermetically entrapped therein gases that maintain the ear stopper 10 in the inflated condition, as illustrated in Fig. Set the drawings.

The end 20, as may be seen in Fig. 8 of the drawings, has a wall thickness that is greater than that of the envelope 12 and the end 16. When the ear stopper 10 is inserted into the external canal 26 of the human ear 18 it assumes the configuration of the external canal 26 and imposes a tight fit therein. By virtue of this tight fit and distortion of the ear stopper 10 the wall 28 between tab 24 and end 29 is expanded outwardly. In other words, the gases entrapped in chamber 14 are compressed in such a manner as to cause an expansion of wall 28. This expansion results in maintaining a tight fit in the external canal 26 of the human ear and also results in a greater than atmospheric pressure being exerted in the external canal between the end 16 of the ear stopper 1% and the ear drum of the human ear.

This greater than atmospheric pressure results in retarding the movement of the ear drum, and by virtue of this fact sound is dampened and the conduction of sound to the middle and inner ear is greatly reduced.

Further, it has been determined that ear stoppers prior to the present invention have placed solids in various forms in chambers similar to that of chamber 14. In-

stead of the solids dampening, reflecting or retarding mixing the liquid polyvinyl chloride plastisol with graphite. In order to obtain a thorough mixture of the two, the polyvinyl chloride plastisol is added to the graphite in a mixing chamber. The thoroughly mixed polyvinyl chloride plastisol and graphite 3th, is then poured into one section 32 of a mold, broadly designated by 34, in the manner as illustrated in Fig. 1 of the drawings. This section of the mold includes that part which forms that portion of the ear stopper 10 between tab 24 and projection 22. Due to the viscosity of the ingredients 30 they do not readily occupy that portion of the mold that has to do with forming the projection 22. Therefore, section 32. is inserted into a vacuum chamber which causes the air occupying cavity 36 of the section 32 to be drawn through the ingredients 30 and, as a result, the polyvinyl chloride plastisol and graphite is enabled to fill and occupy the cavity 36.

Section 38 of the mold 34 is then placed upon section 32 in juxtaposition, as illustrated in Fig. 2 of the drawings. The two sections of the mold are rigidly secured together by bolts 49, or equally applicable structure. It is important to note that the two sections 32 and 38 of the mold 34 must be tightly secured together. If this is not maintained, gases that are to occupy chamber 14 of ear stopper 10 will be permitted to escape from the mold, causing an imperfection to be formed in ear stopper 10. The secured sections of the mold 34 with the ingredients 30 therein are then placed between plates 42 and 44 of a press, broadly designated by 46, as illustrated in Figs. 6 and 7 of the drawings.

Plates 42 and 44 are releasably interconnected by bolts 48 having handles 50 thereon. The purpose of these bolts and handles is to tightly clamp the mold 34 between the plates 42 and 44 of a press. Constructed on each plate 42 and 44 is a heating element 52 and 54.

The press 46 includes a prime mover housing 56 which causes rotation of shaft 58 located thereon and rotation of shaft 66 which interconnects plate 44 with the housing and prime mover located in the housing 56.

The mold 34 being tightly clamped between plates 42 and 44 in the manner as illustrated in Fig. 6 is then caused to be rotated 90 by rotation of shaft 58 to that position illustrated in Fig. 7 of the drawings. In the last-men tioned position shaft 58 then ceases to rotate and shaft 60 is caused to slowly rotate. The slow rotation of shaft 60 results in the liquid polyvinyl chloride plastisol and Each of the graphite flowing from section 32 of the mold around the cavity 62 of section 38 in the manner, as illustrated in Fig. 4 of the drawings. While the polyvinyl chloride plastisol and graphite mixture is fiowable, it does not flow very readily. Consequently, as illustrated in Figs. 3 and 4, when the mold cavity is in its horizontal position as distinguished from the upright position shown in Figs. 1 and 2 some, but not all, of the polyvinyl chloride plastisol flows from that part of the mold which is designed to mold the outer end of the ear stopper into that part of the mold designed to mold the inner end of the ear stopper. Much of the material tends to remain in the mold cavities in the section 32 and, consequently, the wall thickness of the ear stopper at the outer end thereof will be thicker and, consequently, stiffer when the material is ultimately cured. The coating of material that is applied to the walls of the mold cavity in the section 38 is quite thin and will become evenly distributed while the mold cavity and its contents are being rotated in the horizontal position. The walls of the inner end of the ear stopper will, consequently, be quite thin and highly flexible.

\Vhile the mold 34 is slowly being rotated heat is being applied to the mold by heating elements 52 and 54 to cause a coagulation of the polyvinyl chloride plastisol and graphite. The mold 34 is rotated and heated in order to obtain a complete coagulation of the ingredients 30. Although only one portion of the mold is illustrated for forming an ear stopper, it is to be understood that there is provision in each mold for molding any number of ear stoppers 10.

At the completion of the rotating and heating step, the mold 34 is removed from the rotary press 46 and placed in a conventional stationary press in order to obtain a curing of the ingredients 30. This press is usually maintained at a temperature of 350 F. until the polyvinyl chloride plastisol is cured.

Between inserting the mold 24 into the press 46 and the second press a gas is formed by the ingredients heating and rotating which is entrapped in the chamber 14 of the envelope 12 of ear stopper 10. The gas, as aforementioned, maintains the ear stopper It) in an inflated condition and enables the ear stopper 10 to assume a tight fit in the external canal 26 of the ear 18.

Various changes may be made in the details of construction without departing from the spirit and scope of the invention as defined by the appended claim.

I claim:

The method of making ear stoppers which consists of placing a fiowable, heat-curable material in that part of a two part mold which is to mold the outer end of the ear stopper while that part of the mold is in an upright position, closing the mold by applying thereover the other part of the mold which is to mold the inner end of the ear stopper, turning the mold from its upright position to its horizontal position, rotating the mold while in the horizontal position whereby some of the material will fiow from the first-mentioned part of the mold into said other part of the mold to coat the walls of its portion of the mold cavity with a thin layer, heating the mold while thus rotating to coagulate the material, and thereafter curing the material by heatwhereby due to the fact that only part of the material flows from the first-mentioned part of the mold into said other part, the other end of the stopper will have a thicker wall than the inner part of the stopper and the stopper will be hollow except for gases which may be confined therein.

References Cited in the file of this patent UNITED STATES PATENTS 1,344,935 Baum June 29, 1920 2,484,397 Barton Oct. 11, 1949 2,629,134 Molitor Feb. 24, 1953 2,668,985 Babbitt Feb. 16, 1954 2,670,737 Cantor Mar. 2, 1954 

